World-wide occurrence of the suspected mycotoxin producing fungus Drechslera biseptata with grass seed.

A disease of sheep known as "romulosis" occurs in some Australian pastures containing a high percentage of Onion Grass, Romulea rosea Eckl. (Iridaceae). Symptoms of the disease include infertility, abortion and paralysis. Fisher and Finnie (1967) observed that a leaf-spot disease of Onion Grass caused by Drechslera biseptata (Sacc. & Roum.) Richardson & Fraser (= Helminthosporium biseptatum Sacc. & Roum.) was conspicuous among plants growing in toxic pastures. Preliminary feeding trials were conducted to determine if D. biseptata might affect the breeding efficiency of mice and guinea pigs. Addition of the fungus to feed caused significant reduction of breeding efficiency of female mice and male guinea pigs. Fisher and Finnie concluded that under certain conditions the Romulea leaf-spot fungus adversely affects animal reproduction. The nature of the action of D. biseptata was not clarified in this preliminary report but further studies were planned (personal communication, 1970). During a world-wide survey of the microflora of orchard grass seed, Dactylis glomerata L. (1972), we encountered Drechsleria biseptata in 10% of 140 samples of seed from 13 countries. Drechsleria biseptata grew from surface-disinfected seed (1.3% sodium hypochlorite for 10 min) plated on 2% malt agar. Infested samples were from England, France, Netherlands, New Zealand, Sweden and U. S. A. (Oregon). Identification of D. biseptata was confirmed by Dr. M. B. Ellis (Commonwealth Mycological Institute, Kew, England). 1357